The iPhone dev team have released Redsn0w 0.9.6b5 for Mac & Windows which lets you to flash iPad baseband 06.15.00 on iPhone 3G & iPhone 3GS on iOS 4.1.2 or iOS 4.1 stuck at 05.15.04 & 05.14.04 baseband. This is very similar to PwnageTool 4.1.3, but works on both Mac and Windows.

But the good news is that, unlike PwnageTool 4.1.3, iPad 3.2.2 firmware is not required for redsn0w 0.9.6b5 as it fetches iPad iOS 3.2.2 right from Apple servers. You just need to have stock firmware for iOS 4.2.1 for respective devices.

Download RedSn0w 0.9.6b5

Note that if you are using RedSn0w on Windows, you would need to run in Windows XP compatibility mode on Vista & Windows 7.

Download Redsn0w 0.9.6b5 for Windows.

Download Redsn0w 0.9.6b5 for Mac OS X.

If you do flash your baseband via redsn0w, please keep it plugged into USB the whole time. You don’t want your battery to die during the flash process!

Risks involved

There is no way to come back down from 06.15, and there’s no hiding the baseband version from Apple. You’ll be voiding your warranty in a very obvious way.

If some future baseband comes out with a critical fix, you won’t be able to update to it if it remains down in the 05.xx sequence (then again, you wouldn’t update to it if you wanted to keep your unlock anyway).

Starting with FW 4.2.1 if you have 06.15 on your iPhone you won’t ever be able to restore to stock firmware (it will fail). You’ll need to only restore to custom IPSWs (then again, if you’re unlocker you should already be doing that).

Note: This release of Redsn0w is only targeted for iPhone 3GS & 3G users on iOS 4.1 / 4.2.1 who rely on a carrier unlock. If you are using iPhone 4/3GS/3G and not relying on carrier unlock, then follow the instructions posted here in order to jailbreak.

Follow the instructions posted below to update your iPhone 3GS or 3G to 06.15.00 baseband and jailbreak it on iOS 4.1 /4.2.1.

2. Update/Restore to iOS 4.2.1 firmware using the IPSW file you just downloaded via iTunes 10.1.

3. Start Redsn0w 0.9.6b5 and point it to iOS 4.2.1 firmware to proceed with the jailbreak.

4. Select “Install Cydia” & “Install iPad baseband” options and then click “Next” to continue. Redsn0w will now fetch the exploitable 06.15.00 baseband from 3.2.2 firmware and will replace it the baseband in iOS 4.2.1 / 4.1.

Note: Install iPad baseband option is applicable to iPhone 3GS & 3G users only who rely on a carrier unlock.

5. Follow the instructions provided by RedSn0w to enter the DFU mode and wait for it to complete the jailbreaking for you.

Raju is the founder-editor of Technology Personalized. A proud geek and an Internet freak, who is also a social networking enthusiast. You can follow him on Facebook and on Twitter. Mail Raju PP. Follow rajupp